I think the OP wants to manipulate a YAML file with a Perl script (according to the title of the post), so yes, please do check out the various YAML handling modules on CPAN.
My favourite is YAML::Tiny - simple and leight-weight and good for most cases. You would read the YAML file into a Perl data structure, manipulate the data in there and then dump it to a new YAML file (or overwrite the existing one). Have a go and post your code here if you are running into trouble.

topso, I am able to fetch yaml contents but not getting how to make changes in any of the attribute and then save it back.
Actually writing the changes in the .yaml file is becoming a pain.
Can you help in this?